edge (7rheolef)

The edge reference element is K = [0,1].

      0---------1   x

Curved high order Pk edges (k >= 1), in 2d or 3d geometries, are supported. These edges have internal nodes, numbered as:

      0----2----1     0--2--3--1    0-2-3-4-1
          P2              P3           P4

const size_t dimension = 1;
const size_t measure = 1;
const size_t n_vertex = 2;
const point vertex [n_vertex] = {
        point(0),
        point(1) };